Methods and systems for attaching medical device sections

ABSTRACT

Embodiments of the disclosure include methods and systems for attaching an articulation section. In an embodiment, a medical instrument includes a first tubular member including a first end. The medical instrument also includes a second tubular member including a first end. The second tubular member includes a plurality of layers including an inner layer and a first layer including a fluorinated material. The inner layer includes a first section disposed under the first layer and a second section extending out from under the first layer. A portion of the first tubular member overlaps and is bonded to at least a portion of the second section of the inner layer of the second tubular member.

This application claims the benefit of U.S. Provisional Application No.61/592,995, filed Jan. 31, 2012, and U.S. Provisional Application No.61/593,121, filed Jan. 31, 2012, the disclosures of which areincorporated herein in their entirety.

FIELD

The present disclosure relates to a medical device with an articulationsection, and more particularly to methods and systems for attachingmedical device sections.

BACKGROUND

Articulated medical devices provide access to sites within a patient'sbody that are difficult to reach using rigid non-articulating devices.For example, articulated endoscopes provide direct access to internalorgans and articulated catheters provide access to tortuous vascularstructures.

Articulated medical devices have traditionally been flexible to provideeasy manipulation, e.g., to navigate through the lower gastro-intestinaltract. However, it may be difficult to attach an articulation section tothe shaft of the medical device if the articulation section and theshaft are formed with flexible materials.

The methods and systems for attaching an articulation section describedherein overcome these and other limitations of the prior art. Theattachment systems and methods of the present disclosure are broadlyapplicable to various medical devices and other devices requiringarticulation. For example, borescopes use articulation to accessdifficult-to-reach locations within engines or other industrial devices.

Further, a wide variety of medical devices can be employed to assist inperforming endoscopic, laparoscopic, percutaneous, or transluminalprocedures. These devices include operable end-effectors such as, forexample, cutting blades, forceps, graspers, dissectors, scissors, biopsyforceps, or other types of tools.

It is sometimes necessary to utilize one or more end-effectors duringthe course of a procedure. In such instances, it may be both economicaland efficient to replace the end-effector on the device shaft, insteadof replacing the device. It may also be desirable to provide a reusabledevice handle and shaft. Such arrangements may reduce the overall costof the device, and allow for hospital inventory control, as a stockdevice shaft may be provided and any one of multiple end-effectors maybe interchangeably used with the device shaft when necessary. As such,there is a need for a mechanism that permits a quick connection anddisconnection of an end-effector from a device shaft.

SUMMARY

In accordance with an embodiment, a medical instrument includes a firsttubular member including a first end. The medical instrument alsoincludes a second tubular member including a first end. The secondtubular member includes a plurality of layers including an inner layerand a first layer including a fluorinated material. The inner layerincludes a first section disposed under the first layer and a secondsection extending out from under the first layer. A portion of the firsttubular member overlaps and is bonded to at least a portion of thesecond section of the inner layer of the second tubular member.

In accordance with another embodiment, an adapter for an articulationsection includes a body configured to receive a bend portion of a firstarticulation elongate member. The body includes a first end configuredto be attached to an end effector and a second end configured to becoupled to an articulation link of the articulation section. The bodyincludes a first cavity at least partially defined by a first ledge. Thefirst ledge includes a bend configured to support the bend portion ofthe first articulation elongate member. The body also includes at leastone channel extending from the first cavity toward the second end of thebody. The at least one channel is configured to receive portions of thefirst articulation elongate member that are attached to the bendportion. The adapter also includes a first anchoring member configuredto fixedly attach the bend portion of the first articulation elongatemember to the body.

In accordance with yet another embodiment, an adapter for anarticulation section includes a body. The body includes a first endconfigured to be coupled to an articulation link of the articulationsection and a second end configured to be received in an end of atubular member. The body also includes a cavity disposed at the firstend, and the cavity is configured to receive a protrusion in thearticulation link. The body also includes a flange disposed at the firstend, and the flange includes a plurality of first channels configured toalign with corresponding first channels in the tubular member and thearticulation link. The body also includes a tubular portion disposed atthe second end and configured to be received in one of a second channelof the tubular member.

In accordance with an embodiment, medical devices have a separableend-effector and a securing member.

In accordance with another embodiment, a medical device may include anelongate shaft having a proximal end and a distal portion. The medicaldevice may further include an end-effector assembly configured to bereleasably connected to the distal portion of the shaft. The medicaldevice may further include a connection portion, wherein the distalportion of the shaft and a portion of the end-effector assembly form theconnection portion. The medical device may also include a securingmember. The securing member may be movable between a first position awayfrom the connection portion and a second position. In the secondposition, the securing member may be disposed about the connectionportion and configured to connect the end-effector assembly to thedistal portion of shaft.

In accordance with another embodiment, a medical device may include oneor more of the following features: wherein, in the first position, thesecuring member is disposed proximally of the distal portion of theshaft; wherein the securing member has a proximal end that is closer tothe distal portion of the shaft than the proximal end of the shaft;wherein the end-effector assembly includes a clevis having a proximalportion, and wherein the proximal portion of the clevis and the distalportion of the shaft form the connection portion; wherein the securingmember is configured to move relative to the distal portion of the shaftand the end-effector assembly when the proximal portion and the distalportion form the connection portion; wherein the securing memberincludes a retainer, and the proximal portion includes a protrusion, theretainer being configured to receive the protrusion when the securingmember is in the second position; wherein the clevis includes a rim, andwherein a distal end of the securing member abuts the rim in the secondposition.

In accordance with another embodiment, a medical device may include anelongate shaft having a proximal end, a distal portion, and a lumenextending distally from the proximal end to the distal portion. Medicaldevice may also include an elongate member extending through the lumen,the elongate member having a first fitting. An end-effector assembly mayinclude an end-effector and an actuator. The actuator may be connectedto the end-effector and may also have a second fitting. A securingmember may be configured to connect the end-effector assembly to thedistal portion of the shaft when the first fitting is aligned with thesecond fitting.

In accordance with another embodiment, the medical device may includeone or more of the following additional features: wherein theend-effector assembly further includes a clevis having a proximalportion, and wherein the proximal portion and the distal portion form aconnection portion when the first fitting is aligned with the secondfitting; wherein the securing member is configured to move relative tothe distal portion of the shaft and the end-effector assembly when theproximal portion and the distal portion form the connection portion;wherein the securing member includes a retainer configured to receive aprotrusion on the proximal portion of the clevis; wherein the actuatorand the elongate member are adapted to move relative to the lumen of theshaft, when the protrusion is received in the retainer; wherein thesecuring member is disposed on an exterior of the shaft; and wherein thesecuring member has a proximal end that is closer to the distal portionof the shaft than the proximal end of the shaft.

In accordance with another embodiment, a method of assembling a medicaldevice may include aligning an end-effector assembly with a distalportion of a shaft; and engaging a securing member with the end-effectorassembly to secure the end-effector assembly to the distal portion ofthe shaft.

In accordance with another embodiment, a method may include one or moreof the following features: wherein the end-effector assembly includes aclevis having a proximal portion, and wherein aligning the end-effectorassembly with the distal portion of the shaft includes aligning theproximal portion of the clevis and the distal portion of the shaft toform a connection portion; wherein engaging the securing member includesmoving the securing member relative to the distal portion of the shaftand the end-effector assembly when the proximal portion of the clevisand the distal portion of the shaft form the connection portion; whereinthe securing member includes a retainer, and the method furtherincluding coupling the end-effector assembly to the distal end of theshaft by receiving a protrusion on the proximal portion of the clevis inthe retainer; further including disengaging the securing member from theend-effector assembly by moving the securing member relative to thedistal portion of the shaft and the end-effector assembly to decouplethe end-effector assembly from the distal portion of the shaft; andfurther including limiting movement of the securing member relative tothe end-effector assembly.

Additional objects and advantages of the disclosure will be set forth inpart in the description which follows, and in part will be obvious fromthe description, or may be learned by practice of the disclosure. Theobjects and advantages of the disclosure will be realized and attainedby means of the elements and combinations particularly pointed outbelow.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate several embodiments of thedisclosure and together with the description, serve to explain theprinciples of the disclosure.

FIG. 1 is a side view of an instrument assembly, according to anexemplary embodiment;

FIG. 2 is a cross-sectional side view of a distal end of the instrumentassembly of FIG. 1;

FIG. 3 is a perspective view of an end effector in a first position,according to an exemplary embodiment;

FIG. 4 is a perspective view of the end effector of FIG. 3 in a secondposition;

FIG. 5 is a side view of an end effector attached to a distal adapter ofan articulation section, according to an exemplary embodiment;

FIG. 6 is a front view of a body of a distal adapter, according to anexemplary embodiment;

FIG. 7 is a cross-sectional side view of the body of the distal adapterof FIG. 6;

FIG. 8 is a perspective view of a distal adapter including the distaladapter body of FIG. 6;

FIG. 9 is a side view of the distal adapter of FIG. 8;

FIG. 10 is another side view of the distal adapter of FIG. 8;

FIG. 11 is an exploded perspective view of an articulation section,according to an exemplary embodiment;

FIG. 12 is a cross-sectional side view of a proximal adapter of thearticulation section attached to an instrument shaft section, accordingto an exemplary embodiment;

FIG. 13 is a front view of the proximal adapter and instrument shaftsection of FIG. 12;

FIG. 14 is a perspective view of a sheath of an articulation sectionattached to an instrument shaft section, according to an exemplaryembodiment;

FIG. 15 is a cross-sectional perspective view of the sheath of thearticulation section and the instrument shaft section of FIG. 14;

FIG. 16 is a perspective view of a sheath of an articulation sectionattached to an instrument shaft section, according to another exemplaryembodiment;

FIG. 17 is a cross-sectional perspective view of the sheath of thearticulation section and the instrument shaft section of FIG. 16;

FIG. 18 is a perspective view of a sheath of an articulation sectionattached to an instrument shaft section, according to a furtherexemplary embodiment;

FIG. 19 is a cross-sectional perspective view of the sheath of thearticulation section and the instrument shaft section of FIG. 18;

FIG. 20 is a perspective view of a sheath of an articulation sectionattached to an instrument shaft section, according to yet anotherexemplary embodiment;

FIG. 21 is a cross-sectional perspective view of the sheath of thearticulation section and the instrument shaft section of FIG. 20;

FIG. 22 is a perspective view of a medical device in an attachedconfiguration, according to an exemplary embodiment of the disclosure;

FIG. 23 is a perspective view of the medical device of FIG. 22 in adetached configuration, according to an exemplary embodiment of thedisclosure;

FIG. 24A is a perspective view of an end-effector assembly of themedical device of FIG. 22, according to an exemplary embodiment of thedisclosure;

FIG. 24B is a longitudinal cross-section of a clevis of the end-effectorassembly of FIG. 24A, according to an exemplary embodiment of thedisclosure;

FIG. 24C is perspective view of an end-effector, according to anexemplary embodiment of the disclosure;

FIG. 25 is a partial perspective view of a shaft of the medical deviceof FIG. 22 and a securing member disposed on an exterior of the shaft,according to an exemplary embodiment of the disclosure;

FIG. 26A is a partial perspective view of the medical device of FIG. 22with the securing member in a first position, according to an exemplaryembodiment of the disclosure;

FIG. 26B is a partial perspective view of the medical device of FIG. 22with the securing member in a second position, according to an exemplaryembodiment of the disclosure;

FIG. 26C is a cross-section view of FIG. 26B, according to an exemplaryembodiment of the disclosure; and

FIGS. 27A-B illustrate alternative non-limiting end-effector assembliesof the medical device of FIG. 22, according to exemplary embodiments ofthe disclosure.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to exemplary embodiments of thedisclosure, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. Also, anyaspect set forth in any embodiment may be used with any other embodimentset forth herein.

FIGS. 1 and 2 show an instrument assembly 10 according to an exemplaryembodiment. The instrument assembly 10 may be used for any therapeuticor diagnostic endoscopic procedure and the steps thereof. The phrase“endoscopic procedure” is broadly used to indicate any medical procedurethat may be performed by inserting an endoscope, guide tube, catheter,or any other medical device into the body through any anatomic openingor incision. The instrument assembly 10 may be used for performingsurgery at a relative distance from a surgeon. The instrument assembly10 may be adapted for trans-oral, trans-anal, trans-vaginal,trans-urethral, trans-nasal, transluminal, laparoscopic, thorascopic,orthopedic, through the ear, and/or percutaneous access. The componentsof the instrument assembly 10 described below may be made of anysuitable material capable of being inserted into the body, e.g., asuitable biocompatible material.

The terms “proximal” and “distal” are used herein to refer to therelative positions of the components of the exemplary instrumentassembly 10. When used herein, “proximal” refers to a positionrelatively closer to the surgeon using the instrument assembly 10. Incontrast, “distal” refers to a position relatively further away from thesurgeon using the instrument assembly 10 or closer to a surgical sitelocated within the patient's body.

In addition, while the discussion of systems and methods below maygenerally refer to “surgical instruments,” “surgery,” or a “surgicalsite” for convenience, the described systems and their methods of useare not limited to tissue resection and/or repair. In particular, thedescribed systems may be used for inspection and diagnosis in addition,or as an alternative, to surgical treatment. The treatment is notlimited to any particular treatment. Various other exemplary treatmentdevices and methods are referred to herein. Moreover, the systemsdescribed herein may perform non-medical applications such as in theinspection and/or repair of machinery.

The instrument assembly 10 may be configured to be advanced through anyanatomical opening and/or body lumen. For example, the instrumentassembly 10 may be used in natural orifice transluminal endoscopicsurgery (NOTES) procedures or single incision laparoscopic surgical(SILS) procedures. Accordingly, the instrument assembly 10 may be shapedand sized for placement into a patient via a body cavity or an incision.

The instrument assembly 10 may have a distal end 12 and a proximal end14. In order from the distal end 12 to the proximal end 14, theinstrument assembly 10 may include an end effector 20 (FIGS. 3 and 4),an articulation section 30, and an instrument shaft section 60.

The proximal end 14 of the instrument assembly 10 may include variousmechanisms for allowing the user to control the distal end 12 of theinstrument assembly 10. The proximal end 14 may include one or moreknobs, handles, control members, or other devices configured to move thedistal end 12 relative to the proximal end 14. For example, a knob 100may control the movement of the distal end 12 along a distal directionand proximal direction, or rotationally relative to the proximal end 14.Some exemplary components for controlling movement of the distal end ofan instrument assembly are disclosed, for example, in U.S. PatentApplication Publication No. 2008/0188868, entitled “Direct DriveEndoscopy Systems and Methods” and the U.S. Provisional Application No.61/593,209, both of which are hereby incorporated by reference in theirentirety.

One or more actuation control members 102 (e.g., with or without one ormore grippers) may control the actuation of the end effector 20. Thecontrol member 102 can include a wire, a cable, a ribbon, or similarelongate structure. In the exemplary embodiment shown in FIG. 1, oneactuator control member 102 is provided. For example, the actuatorcontrol member 102 may allow the operator to actuate the end effector 20when the actuator control member 102 is pulled in the proximal directionor pushed in the distal direction. The actuator control member 102 mayalso be configured to transmit an electrical current to the distal end12.

One or more articulation control members may control the articulation ofthe articulation section 30 as described below. For example, thearticulation control members may be braided wire. In the exemplaryembodiment shown in FIG. 1, the instrument assembly 10 may include twoarticulation control members. Each articulation control member mayextend from the proximal end 14 of the instrument assembly 10 to adistal adapter 300 (described below) of the articulation section 30,where the articulation control member bends and extends back to theproximal end 14 of the instrument assembly 10. Thus, one articulationcontrol member may include two articulation control member portions 111and 112 and a bend portion 116 (FIGS. 2, 5, and 8-10) connecting theportions 111 and 112. The other articulation control member may alsoinclude two articulation control member portions 113 and 114 and anotherbend portion 116 connecting the portions 113 and 114. The fourarticulation control member portions 111, 112, 113, and 114 may controlarticulation of the articulation section 30 in four directions (e.g.,right, up, left, and down, respectively). For example, when the operatorpulls the first articulation control member portion 111 or 113 in theproximal direction, the articulation section 30 may be articulated inthe right or left direction, respectively. When the operator pulls thefirst articulation control member portion 112 or 114 in the proximaldirection, the articulation section 30 may be articulated in the up ordown direction, respectively. Alternatively, the instrument assembly 10may include one articulation control member, or more than twoarticulation control members, depending on a desired range of movementof the instrument assembly 10.

FIGS. 3 and 4 show the end effector 20 in the form of a pair of scissorsaccording to an exemplary embodiment. Alternatively, the end effector 20may include a grasper, a hook, an ablation device, or other type ofsurgical or electrosurgical instrument configured to operate with, orinclude, insufflation, irrigation, suction, imaging, or other devicesused in endoscopic, laparoscopic, or other surgical procedures. In theexemplary embodiment, the end effector 20 may be formed of a rigidmaterial, such as stainless steel.

The distal end of the end effector 20 of the exemplary embodiment mayinclude scissor blade portions 200, which are pivotally attached by apivot pin 202 to a clevis 204 at a proximal end of the end effector 20.The proximal end of the clevis 204 may be received in and attached to adistal end of the articulation section 30. The scissor blade portions200 also pivotally attach to an actuator 206 slidably disposed in theclevis 204. A distal end of the actuator 206 may be pivotally attachedto respective grooves (not shown) in the scissor blade portions 200 viaa link pin (not shown). A proximal end of the actuator 206 may beattached (e.g., by welding) to the distal end of the actuation controlmember 102 that extends to the proximal end 14 of the instrumentassembly 10 to allow the operator to control the actuation of the endeffector 20. For example, FIG. 3 shows the actuator 206 in a normalposition with the scissor blade portions 200 closed. In this position,when the operator pushes the actuation control member 102 in the distaldirection, the actuator 206 may slide in the distal direction relativeto the clevis 204, thereby causing the link pin to slide within thegrooves in the scissor blade portions 200 and causing the scissor bladeportions 200 to open. When the operator pulls back the actuation controlmember 102, the actuator 206 may slide in the proximal directionrelative to the clevis 204, thereby causing the scissor blade portions200 to close.

The proximal end of the clevis 204 may include one or more proximalprotrusions 208 configured to be inserted into corresponding notches inthe distal end of the articulation section 30 as described below. In theexemplary embodiment shown in FIGS. 3 and 4, the clevis 204 includes twoproximal protrusions 208. The two proximal protrusions 208 may bedisposed on opposite sides of the clevis 204 with respect to alongitudinal axis of the clevis 204 and the end effector 20. The shapeof the proximal protrusions 208 may correspond to notches formed betweencorresponding distal protrusions 308 (FIGS. 5-10) as described below.

The end effector 20 may be connected to a distal adapter 300 at thedistal end of the articulation section 30. The articulation section 30may also include a series of articulation links 400 and a proximaladapter 500 (FIGS. 13, 15, 17, 19, and 21) for connecting to theinstrument shaft section 60. Some exemplary configurations ofarticulation links and articulation sections are disclosed, for example,in U.S. Provisional Application No. 61/438,072 and U.S. patentapplication Ser. No. 13/360,018, both entitled “Articulation Joints forTorque Transmission,” both of which are hereby incorporated by referencein their entirety.

FIG. 5 shows the proximal end of the clevis 204 of the end effector 20attached to the distal adapter 300, according to an exemplaryembodiment. The distal adapter 300 may include a body 301 and one ormore anchoring members 330 that may fix the bend portions 116 of thearticulation control members to the body 301. Each of the articulationcontrol member portions 111, 112, 113, and 114 may extend in theproximal direction from the distal adapter 300.

FIGS. 6 and 7 show the body 301 of the distal adapter 300, according toanother exemplary embodiment, and FIGS. 8-10 show the distal adapter 300including the body 301 and two anchoring members 330, according to anexemplary embodiment. The body 301 includes a distal end 302, a proximalend 304, and a longitudinal axis 306 extending between the distal andproximal ends 302 and 304. In the exemplary embodiment, the body 301 maybe formed of a rigid material, such as stainless steel or a polymer,such as a polyamid. Also, in an exemplary embodiment, the length orlongitudinal dimension of the body 301 (e.g., the distance between thedistal end 302 and the proximal end 304) may be less than or equal toapproximately 0.16 inches.

The distal end 302 of the body 301 may include one or more distalprotrusions 308 configured to engage and interlock with the proximalprotrusions 208 (FIGS. 3 and 4) in the end effector 20. In the exemplaryembodiment shown in FIGS. 5-10, the body 301 includes two distalprotrusions 308. The two distal protrusions 308 may be disposed onopposite sides of the body 301 with respect to the longitudinal axis306. The shape of the distal protrusions 308 may correspond to notchesformed between the corresponding proximal protrusions 208 of the endeffector 20. For example, each distal protrusion 308 may include onesurface that may contact and be substantially flush against one proximalprotrusion 208, and an opposite surface that may contact and besubstantially flush against the other proximal protrusion 208. Engagingthe proximal protrusions 208 with the distal protrusions 308 may permittorque transfer between the end effector 20 and the articulation section30. The proximal protrusions 208 and the distal protrusions 308 may alsobe attached together (e.g., by welding or bonding) to attach the endeffector 20 to the distal adapter 300.

The distal end 302 of the body 301 may also include a distal cavity 310.The distal cavity 310 may be configured to receive the proximal end ofthe actuator 206 of the end effector 20 when the actuator 206 is pulledin the proximal direction relative to the clevis 204 of the end effector20, as described above.

The proximal end 304 of the body 301 may include a proximal protrusion312 configured to be coupled or attached to the distalmost articulationlink 400 of the series of articulation links 400. In the exemplaryembodiment, the proximal protrusion 312 may be rectangular and may bereceived within a corresponding rectangular cavity in the distalmostarticulation link 400. As shown in FIGS. 9 and 10, the proximalprotrusion 312 may also include a curved proximal surface (e.g., concaveor curved outward toward the proximal direction) to allow the distaladapter 300 to engage a corresponding curved surface (e.g., convex orcurved inward) of the distalmost articulation link 400.

As shown in FIGS. 6 and 7, the body 301 of the distal adapter 300 mayalso include one or more actuator control member channels 314. In theexemplary embodiment, the body 301 includes one actuator control memberchannel 314 that has an axis that is substantially collinear with thelongitudinal axis 306 of the body 301. The actuator control memberchannel 314 may connect to the distal cavity 310, which also has an axisthat is collinear with the longitudinal axis 306 of the body 301 and mayhave a different width or lateral dimension (e.g., diameter) than theactuator control member channel 532. For example, as shown in FIGS. 6and 7, the actuator control member channel 314 may have a smallerdiameter than the distal cavity 310. The distal cavity 310 and theactuator control member channel 314 may slidably receive the actuatorcontrol member 102 (FIGS. 1, 3, and 4) to allow the actuator controlmember 102 to pass through the distal adapter 300.

The body 301 of the distal adapter 300 may also include one or morecavities 320 for supporting the one or more articulation control membersreceived by the body 301. In the exemplary embodiment, the body 301includes two side cavities 320 positioned at opposite sides of the body301 relative to the longitudinal axis 306. Each side cavity 320 may bepartially defined by a respective pedestal or ledge 322 and an innersurface 324. The inner surface 324 may extend generally along thedirection of the longitudinal axis 306 and may have a diameter D (FIG.6) measured along a plane perpendicular to the longitudinal axis 306. Asshown in FIG. 6, the diameter D may be smaller than an outer diameter ofthe body 301. The ledges 322 may form a curved surface such that anouter surface of the curve faces the distal direction (e.g., concave orcurved outward toward the distal direction).

In the exemplary embodiment shown in FIGS. 6-10, the ledges 322 andinner surfaces 324 may support the respective articulation controlmember (e.g., the bend portions 116) received in the body 301.Alternatively, in the exemplary embodiment shown in FIG. 5, the bendportions 116 may be supported by the inner surfaces 324 and may extenddistal to the ledges 322. In both embodiments, the bend portions 116 mayremain proximal to the distal end 302 of the body 301 without protrudingfrom the distal end 302 of the body 301.

The distal adapter 300 may support the bend portions 116 of thearticulation control members so that the articulation control members donot form a kink. In the exemplary embodiment shown in FIGS. 6-10, toreduce the likelihood of forming kinks, the ledges 322 may be formed aselliptical arcs (portions of ellipses), and the dimensions of theelliptical arcs may depend on a dimension of the distal adapter 300(e.g., the diameter D (FIG. 6)) and/or a configuration of thearticulation control member (e.g., the size of the braid).Alternatively, the ledges 322 may form another type of curved bendinstead of an elliptical arc, such as a semicircular bend, thedimensions of which may also depend on a dimension of the distal adapter300 and/or a configuration of the articulation control member.

Referring to FIGS. 6 and 7, each side cavity 320 may connect to one ormore articulation control member channels 326. The articulation controlmember channels 326 may extend from the side cavities 320 to the outersurface of the body 301 from which the proximal protrusion 312 extends.In the exemplary embodiment shown in FIGS. 6-10, the body 301 includesfour articulation control member channels 326 positioned atapproximately 0, 90, 180, and 360 degrees, respectively, about theactuator control member channel 320 relative to the longitudinal axis306. The articulation control member channels 326 may slidably receivethe respective articulation control member portions 111, 112, 113, and114 that are proximal to the bend portions 116 to allow the articulationcontrol member portions 111, 112, 113, and 114 to extend in the proximaldirection from the distal adapter 300.

FIGS. 8-10 show the anchoring members 330 disposed within the sidecavities 320, respectively. The anchoring members 330 may be formed inthe side cavities 320 after the articulation control members (e.g., thebend portions 116) are positioned on the respective ledges 322 and/orthe inner surfaces 324. The anchoring members 330 may be attached to thebody 301 by adhesion or cohesion, e.g., using an adhesive or a polymer.In an exemplary embodiment, the anchoring members 330 may be formed byepoxy (e.g., a one- or two-part epoxy) or other thermosetting polymerthat may be inserted into and at least partially fill the side cavities320 to fix the bend portions 116 to the ledges 322 and/or the innersurfaces 324. Alternatively, the anchoring members 330 may be formed bypolyether ether ketone (PEEK), solder, or other material capable ofmelting at a temperature that is lower than the melting point of thematerial forming the body 301. In an exemplary embodiment, the anchoringmembers 330 may be formed so that an outer surface of the anchoringmembers 330 and an outer surface of the body 301 form a generallycylindrical outer surface, as shown in FIGS. 5 and 8-10. The anchoringmembers 330 may substantially cover the bend portions 116 and fix thebend portions 116 to the respective ledges 322 and/or inner surfaces324. The anchoring members 330 may also be substantially entirelydisposed between the distal or proximal ends 302 and 304.

In another exemplary embodiment, the proximal end of the clevis 204 maybe received in and attached to, or uncoupled from, a distal end of thearticulation section 30, in the manner shown in FIGS. 22-27B. Forexample, the proximal end of the clevis 204 may include a pair of armsand a shape and/or configuration similar to a proximal portion 740. Thedistal end of the distal adapter 300 may have shape and/or configurationsimilar to a distal portion 722. The proximal end of the clevis 204 andthe distal end of the adapter 300 may have complementary shapes and/orconfigurations, similar to the proximal portion 740 and distal portion722.

The actuator control member 102 may include a distal portion similar toa distal portion of an elongate member 726, and may also include a firstfitting similar to a first fitting 730. The actuator 206 may include aproximal portion similar to a proximal portion of an actuator 738, andmay also include a second fitting similar to the second fitting 732. Theactuator 206 and the actuator control member 102 may couple and uncouplein the same way the elongate member 726 and the actuator 738 may couple

The proximal end of the clevis 204 of the end effector 20 may beattached to the distal end of the distal adapter 300 by a securingmember similar to a securing member 718. For example, a distal end ofthe securing member may include a retainer having a recess, similar to adistal end 758 of the securing member 718, a retainer 760, and a recess761, respectively. The recess may be configured to receive a protrusionon a proximal portion of the clevis 204, similar to a protrusion 762 ona proximal portion 740 of a clevis 734. The securing member may movedistally relative to the distal end of the distal adapter 300 when theproximal portion of the clevis 204 and the distal portion of the distaladapter 300 are aligned, to form a substantially cylindrical jointsimilar to a joint 763.

When the securing member is moved distally, the recess of the retainermay receive the protrusion on the proximal portion of the clevis 204,similar to the way the securing member 718 moves distally so the recess761 of the retainer 760 may receive the protrusion 762 on the proximalportion 740 of the clevis 734. When the protrusion is received in therecess of the retainer, a radial force may be exerted on the firstfitting and the second fitting to couple the first fitting and thesecond fitting, similar to coupling of the first fitting 730 and thesecond fitting 732. When the first and second fittings are coupled, theactuator 206 and the actuator control member 102 may be used to actuatethe end effector 20. Further aspects that may be used in thisembodiment, including connection features, and steps for coupling anduncoupling, are described below in sections referencing FIGS. 22-27B. Itshould be understood that any of the features in FIGS. 22-27B, eitheralone or in combination, may be used interchangeably with the featuresin FIGS. 1-21.

After fixing the articulation control members to the distal adapter 300,the articulation control member portions 111, 112, 113, and 114 may beinserted through corresponding channels in the plurality of articulationlinks 400 to allow the articulation control member portions 111, 112,113, and 114 to pass through the articulation links 400. FIG. 11 showsthe insertion of the articulation control member portions 111, 112, 113,and 114 through the plurality of articulation links 400 prior topositioning the articulation links 400 together as shown in FIG. 2. Asshown in FIGS. 2 and 11, each articulation link 400 may include asubstantially cylindrical outer surface, and may include a cavity 402 onits distal end and a protrusion 404 on its proximal end. Eacharticulation link 400 may also be coated with an insulative material.The protrusions 404 of each articulation link 400 may have a similarshape as the proximal protrusion 312 of the distal adapter 300. When thearticulation control members connect the distal adapter 300 to thearticulation links 400, the proximal protrusion 312 of the distaladapter 300 may be inserted into the cavity 402 in the distalmost(first) articulation link 400, the protrusion 404 on the firstarticulation link 400 may be inserted into the cavity 402 in the secondarticulation link 400, the protrusion 404 on the second articulationlink 400 may be inserted into the cavity 402 in the third articulationlink 400, etc. In an exemplary embodiment, the protrusions 404 of thearticulation links 400 may be generally rectangular. The cavities 402 inthe articulation links 400 may be defined by one or more inner surfaces,and may be generally rectangular in order to receive the correspondingprotrusions 312, 404. Alternatively, the cavities 402 and protrusions312, 404 may have another shape. The distal adapter 300, thearticulation links 400, and the proximal adapter 500 allow thearticulation section 30 to articulate as described above.

Each articulation link 400 may also include an inner surface definingone or more actuator control member channels 406. In the exemplaryembodiment, each articulation link 400 includes one actuator controlmember channel 406 having an axis substantially collinear with alongitudinal axis of the articulation link 400 and extending through thearticulation link 400. The actuator control member channel 406 mayslidably receive the actuator control member 102 (FIGS. 1, 3, and 4) toallow the actuator control member 102 to extend between the end effector20 and the proximal end 14 of the instrument assembly 10.

FIGS. 12 and 13 show the proximal adapter 500 of the articulationsection 30. The proximal adapter 500 may connect to the distal end ofthe instrument shaft section 60. The proximal adapter 500 may include abody 501 including a distal end 502, a proximal end 504, and alongitudinal axis 506 extending between the distal and proximal ends 502and 504. In the exemplary embodiment, the body 501 may be formed of arigid material, such as stainless steel or a polymer, such as apolyamid. Also, in an exemplary embodiment, the length or longitudinaldimension of the body 501 may be less than or equal to approximately0.12 inches.

The distal end 502 of the body 501 may include a distal cavity 510 sizedto receive the protrusion 404 on the proximalmost articulation link 400.In the exemplary embodiment shown in FIGS. 12 and 13, the distal cavity510 may be defined by one or more inner surfaces, and may have the sameshape (e.g., rectangular) as the protrusion 404 on the proximalmostarticulation link 400 in order to receive the protrusion 404.

The distal end 502 of the body 501 may also include a flange 520. Theflange 520 may be generally cylindrical and may include a plurality ofarticulation control member channels 522 extending between the distaland proximal surfaces of the flange 520. In the exemplary embodiment,the flange 520 may include four articulation control member channels 522that may be spaced from each other. For example, the four articulationcontrol member channels 522 may be positioned at approximately 0, 90,180, and 360 degrees, respectively, about the distal cavity 510 relativeto the longitudinal axis 506, or at other angles. The articulationcontrol member channels 522 may slidably receive the respectivearticulation control member portions 111, 112, 113, and 114 to allow thearticulation control member portions 111, 112, 113, and 114 to passthrough the proximal adapter 500.

The proximal end 504 of the body 501 may include a tubular portion 530that extends from the flange 520 in the proximal direction. The tubularportion 530 may have a substantially cylindrical outer surface and mayinclude an inner surface defining one or more actuator control memberchannels 532. In the exemplary embodiment shown in FIGS. 12 and 13, thebody 301 may include one actuator control member channel 532 having anaxis substantially collinear with the longitudinal axis 506 of the body501. The actuator control member channel 532 may be substantiallycylindrical and may connect to the distal cavity 510, which also has anaxis that may be collinear with the longitudinal axis 506 of the body501 and may have a different width or lateral dimension (e.g., diameter)than the actuator control member channel 532. For example, as shown inFIGS. 12 and 13, the actuator control member channel 532 may have adiameter that is smaller than the dimensions of the distal cavity 510.The distal cavity 510 and the actuator control member channel 532 mayslidably receive the actuator control member 102 (FIGS. 1, 3, and 4) toallow the actuator control member 102 to extend between the end effector20 and the proximal end 14 of the instrument assembly 10. In anexemplary embodiment, the length or longitudinal dimension of thetubular portion 530 (e.g., the distance between the proximal surface ofthe flange 520 to the proximal surface of the tubular portion 530) maybe less than or equal to approximately 0.10 inches. As shown in FIG. 12,the tubular portion 530 of the proximal adapter 500 may be inserted intothe instrument shaft section 60.

In an exemplary embodiment, the instrument shaft section 60 may includean outer first layer 610 (FIGS. 14-21), a second layer 620, a thirdlayer 630, and a catheter or inner tubular portion 640 forming a fourthlayer. The inner tubular portion 640 may be formed of a flexiblematerial, such as a polymer, polyamide, etc. In an exemplary embodiment,the inner tubular portion 640 may be formed of nylon (e.g., nylon 12,RILSAN® AESNO) extruded to form the inner tubular portion 640.

As shown in FIG. 12, the inner tubular portion 640 may have a generallycylindrical outer surface and may have a longitudinal axis 642. Theinner tubular portion 640 may also include a plurality of lumens orchannels. For example, the inner tubular portion 640 may include one ormore actuator control member channels 644, and one or more articulationcontrol member channels 646. In the exemplary embodiment shown in FIG.12, the inner tubular portion 640 includes one actuator control memberchannel 644 having an axis substantially collinear with the longitudinalaxis 642. The actuator control member channel 644 may be generallycylindrical and may slidably receive the actuator control member 102(FIGS. 1, 3, and 4). The tubular portion 530 of the proximal adapter 500may be inserted into the actuator control member channel 644 of theinner tubular portion 640 so that the actuator control member channel644 may align with the actuator control member channels 314, 406, and532 in the distal adapter 300, the articulation links 400, and theproximal adapter 500. As a result, the actuator control member 102 maypass through the actuator control member channels 314, 406, 532, and 644to extend between the end effector 20 and the proximal end 14 of theinstrument assembly 10.

Also, the inner tubular portion 640 may include four articulationcontrol member channels 646 that may be spaced from each other. Forexample, the four articulation control member channels 646 may bepositioned at approximately 0, 90, 180, and 360 degrees, respectively,about the actuator control member channel 644 relative to thelongitudinal axis 642, or at other angles. The articulation controlmember channels 646 may slidably receive the respective articulationcontrol member portions 111, 112, 113, and 114. When the tubular portion530 of the proximal adapter 500 is inserted into the inner tubularportion 640, the articulation control member channels 646 may align withthe articulation control member channels 326 and 522 in the distaladapter 300, the articulation links 400, and the proximal adapter 500 toallow the articulation control member portions 111, 112, 113, and 114 toextend between the distal adapter 300 and the proximal end 14 of theinstrument assembly 10.

The tubular portion 530 of the proximal adapter 500 may be inserted intothe inner tubular portion 640 until a proximal surface of the flange 520of the proximal adapter 500 abuts the distal end of the inner tubularportion 640.

The outer dimension (e.g., outer diameter) of the tubular portion 530 ofthe proximal adapter 500 may be larger than the dimension (e.g.,diameter) of the actuator control member channel 644 of the innertubular portion 640 before the tubular portion 530 is inserted into theinner tubular portion 640. Thus, although the inner tubular portion 640may be formed with a substantially constant outer diameter and innerdiameter, the insertion of the tubular portion 530 of the proximaladapter 500 may cause the inner tubular portion 640 to expand radially,as shown in FIG. 12. As a result, the inner tubular portion 640 mayprovide a radial pressure or force on the tubular portion 530 of theproximal adapter 500 such that the tubular portion 530 may be held inplace in the inner tubular portion 640 (e.g., to assist in preventingthe tubular portion 530 from inadvertently slipping out of the innertubular portion 640).

The outer surface of the tubular portion 530 of the proximal adapter 500may include one or more circumferential ribs 534. In the exemplaryembodiment shown in FIG. 12, the tubular portion 530 includes three ribs534, and the ribs 534 extend around substantially the entirecircumference of the tubular portion 530. Alternatively, the ribs 534may extend around a portion of the circumference. The ribs 534 mayassist in maintaining the tubular portion 530 anchored in the innertubular portion 640 of the instrument shaft section 60, e.g., byproviding resistance to movement of the tubular portion 530 in thelongitudinal direction.

The tubular portion 530 of the proximal adapter 500 may also include oneor more notches 536. In the exemplary embodiment shown in FIG. 12, thetubular portion 530 includes one notch 536 extending generally parallelto the longitudinal axis 506 (FIG. 13). The notch 536 may extend alongthe radial direction through the tubular portion 530. The notch 536 mayalso extend along the longitudinal direction from the proximal end 504of the body 501 past at least one of the ribs 534 (e.g., one, at leasttwo, or all of the ribs 534). The notch 536 may assist in maintainingthe tubular portion 530 anchored in the inner tubular portion 640 of theinstrument shaft section 60, e.g., by providing resistance to torsionalmovement of the tubular portion 530.

The third layer 630 of the instrument shaft section 60 may be areinforcement or stiffening layer that overlies the inner tubularportion 640. For example, the third layer 630 may include a braidedconfiguration of tightly wound wires or polymeric elements, such asstainless steel braid. As shown in FIG. 12, the third layer 630 maycover a majority of the inner tubular portion 640 (e.g., an intermediateportion of the inner tubular portion 640), but may leave a portion ofthe inner tubular portion 640 uncovered (e.g., the distal end and/or theproximal end of the inner tubular portion 640). In an exemplaryembodiment, the inner tubular portion 640 may be uncovered along alength of at least approximately 0.14 inches from the distal edge of theinner tubular portion 640. Alternatively, the length of the uncoveredportion may depend on the length of the tubular portion 530 of theproximal adapter 500, e.g., so that the length of the uncovered portionis at least as long as the length of the tubular portion 530. As aresult, the uncovered distal end of the inner tubular portion 640 may befree to expand, and may not be restricted by the third layer 630, thesecond layer 620, and/or any other additional layers, when the tubularportion 530 is inserted into the uncovered distal end of the innertubular portion 640.

The second layer 620 of the instrument shaft section 60 may be formed ofone or more polymers, such as a thermoplastic elastomer (e.g., PEBAX®).In an exemplary embodiment, the second layer 620 may be formed fromPEBAX® 7233 or 6233. The second layer 620 may be formed by extrusioncoating onto the third layer 630. As shown in FIG. 12, the second layer620 may cover substantially the entire third layer 630.

As shown in FIGS. 14-21, the instrument shaft section 60 may alsoinclude the first layer 610. The first layer 610 may be formed of one ormore fluoropolymers, such as fluorinated ethylene propylene (FEP),polytetrafluoroethylene (PTFE), perfluoroalkoxy (PFA), ethylenetetrafluoroethylene (ETFE), or other fluorinated material orfluoropolymer. Alternatively, or in addition, the first layer 610 may beformed of one or more other polymers, such as polyethylene, high-densitypolyethylene (HDPE), polyethylene terephthalate (PET), polyimide, etc.The first layer 610 may be formed by molding, heat shrinking, orextrusion onto the second layer 620. Alternatively, the first layer 610may be formed by coating (e.g., dip coating) onto the second layer 620.

The first layer 610 may be formed of an insulative material, such as amaterial having a relatively high dielectric strength, a relatively lowdielectric constant, and/or a relatively high melting temperature, suchas FEP or other fluorinated material. Providing the first layer 610 overthe third layer 630 (e.g., a stainless steel braided layer, according toan embodiment) may improve the insulation of the instrument assembly 10.For example, the first layer 610 may serve as a barrier thatelectrically insulates electrically conductive components in theinstrument shaft section 60 (e.g., the third layer 630) from othercomponents that may carry an electric current, such as a metal tip of anelectrosurgical instrument used in conjunction with the instrumentassembly 10. As a result, the first layer 610 may limit possible burningof the patient or damage to the instrument assembly 10 or theelectrosurgical instrument due to the inadvertent conduction ofelectrical current.

Also, in an exemplary embodiment, the first layer 610 may have a higherdielectric strength, lower dielectric constant, and/or higher meltingtemperature than the second layer 620 (e.g., PEBAX®, according to anembodiment).

For example, the first layer 610 may be formed of FEP or otherfluorinated material having a relatively low dielectric constant and arelatively high melting temperature (e.g., compared to PEBAX® or othermaterial forming the second layer 620 or other portion of the instrumentshaft section 60). The dielectric constant may correspond to thematerial's ability to polarize in an electric field. In atime-alternating electric field, molecules may heat up due to thereorientation of the molecules. A material with a relatively highdielectric constant and a relatively low melting temperature may heat upand exceed its melting temperature. Therefore, a material with arelatively low dielectric constant and a relatively high meltingtemperature may be desirable. For example, fluoropolymers havingrelatively low dielectric constants and relatively high meltingtemperatures include FEP (having a dielectric constant of approximately2.1), PTFE (having a dielectric constant of approximately 2.1), PFA(having a dielectric constant of approximately 1.9 to approximately2.1), and ETFE (having a dielectric constant of approximately 2.5 toapproximately 2.6). Another polymer having a relatively low dielectricconstant and relatively high melting temperature is polyethylene (havinga dielectric constant of approximately 2.3). In comparison, PEBAX® has adielectric constant of approximately 4.0. Accordingly, it may bedesirable to form the first layer 610 of a material having a dielectricconstant of less than approximately 3.0, or less than approximately 3.5.The dielectric constants identified above are provided for materials ata frequency of 1 MHz.

The first layer 610 may also provide a relatively high dielectricstrength. For example, the first layer 610 may be formed of FEP or otherfluorinated material having a relatively high dielectric strength (e.g.,compared to PEBAX® or other material forming the second layer 620 orother portion of the instrument shaft section 60). The dielectricstrength may correspond to the amount of voltage a material is able towithstand without breaking down. For example, the first layer 610 may beformed of FEP (having a dielectric strength that may be approximately2000 V/inch in some applications), PFA (having a dielectric strengththat may be approximately 2000 V/inch in some applications), or ETFE(having a dielectric strength that may be approximately 1800 V/inch insome applications). In comparison, PEBAX® may have a dielectric strengthof approximately 1130 V/inch in some applications.

Optionally, additional layers may be provided between the first layer610 and the inner tubular portion 640. For example, a layer or coatingof PEBAX® 2533 or other thermoplastic elastomer, or other polymer may beprovided between the third layer 630 and the inner tubular portion 640.

As shown in FIGS. 14-21, the articulation section 30 may also include acover or sheath 410 that covers at least a portion of the articulationsection 30 (e.g., the distal adapter 300, the articulation links 400,and/or the proximal adapter 500). The sheath 410 may be formed of one ormore polymers, such as thermoplastic polyurethane (e.g., PELLETHANE®) orother polyurethane plastic or elastomer, or other thermoplasticelastomer, or other flexible polymer. The sheath 410 may be formed of amaterial, such as a layer of PELLETHANE®, that is relatively difficultto tear and is flexible.

The sheath 410 may act as a barrier between the patient and thecomponents of the articulation section 30 (e.g., the distal adapter 300,the articulation links 400, and/or the proximal adapter 500). Forexample, the sheath 410 may limit occlusion formation in extracellularfluid (e.g., blood cell clumps) of the patient within the articulationsection 30. Occlusions in the articulation section 30 may reduce theability to articulate and/or actuate the instrument assembly 10.

The material used for forming the sheath 410 may be flexible. As theinstrument assembly 10 articulates, the sheath 410 may be able tostretch and maintain a higher durometer (hardness) to prevent breakageof the sheath 410. As a result, the sheath 410 may be thinner, which mayallow the operator to more easily insert the instrument assembly 10 inthe patient.

Also, the sheath 410 may serve as a barrier that electrically insulateselectrically conductive components in the articulation section 30 (e.g.,the distal adapter 300, the articulation links 400, and/or the proximaladapter 500) from other components that may carry an electric current,such as a metal tip of an electrosurgical instrument used in conjunctionwith the instrument assembly 10. As a result, the sheath 410 may preventpossible burning of the patient or shocks to the surgeon due to theinadvertent conduction of electrical current through the instrumentassembly 10.

As described below in connection with FIGS. 14-21, at least a portion ofthe sheath 410 may overlap and bond to at least a portion of theinstrument shaft section 60, e.g., so that the sheath 410 and the firstlayer 610 of the instrument shaft section 60 can provide a continuousflexible and/or insulative barrier.

Depending on the materials used to form the sheath 410 and the firstlayer 610 of the instrument shaft section 60, it may be difficult toadhere the sheath 410 and the first layer 610 together. For example,inert or lubricious materials (e.g., materials having a low surfaceenergy or coefficient of friction) may be difficult to adhere to othermaterials, and in an exemplary embodiment, the first layer 610 may beformed of a material, such as FEP or other fluorinated material, whichis inert or lubricious. On the other hand, the instrument shaft section60 may include other layers (e.g., the second layer 620, the innertubular portion 640, etc.) formed of materials that may be lessdifficult to adhere to other materials. For example, the second layer620 may be formed of PEBAX® and the inner tubular portion 640 may beformed of nylon.

FIGS. 14-21 show various exemplary embodiments in which the sheath 410of the articulation section 30 may be attached to the instrument shaftsection 60. The sheath 410 may include at least a portion 414, 416(FIGS. 15, 17, 19, and 21) that overlaps and may be attached (e.g.,using an adhesive) to a component of the instrument shaft section 60that may be formed of a material that is not lubricious (e.g., anon-fluorinated material), as described below. As a result, the sheath410 may be attached to the instrument shaft section 60 to form with theouter first layer 610 a continuous and flexible barrier to fluids andelectrical current.

According to an embodiment, as shown in FIGS. 14 and 15, a proximal endportion 414 of the sheath 410 may be attached to the second layer 620 ofthe instrument shaft assembly 60.

The first layer 610 of the instrument shaft section 60 may be formed onthe second layer 620 so that at least a portion of the second layer 620(e.g., a distal end portion) is exposed. For example, the first layer610 may be initially formed so that the entire second layer 620 iscovered by the first layer 610. Then, the distal end portion of thefirst layer 610 may be removed (e.g., by centerless grinding or otherremoval method) to uncover the underlying portion of the second layer620. Alternatively, the first layer 610 may be applied only on aproximal portion of the second layer 620.

Thus, prior to attaching the sheath 410 to the instrument shaft section60, the distal end portion of the second layer 620 may be exposed. Then,the proximal end portion 414 of the sheath 410 may be placed over theexposed distal end portion of the second layer 620 so that the proximaledge of the sheath 410 may meet and abut a distal edge of the firstlayer 610 to form a meeting point or junction 650 between the sheath 410and the first layer 610. The proximal end portion 414 of the sheath 410may overlie the second layer 620 and may be bonded to the second layer620, e.g. using an adhesive, such as a cyanoacrylate, an epoxy (e.g., atwo-part epoxy), or an ultraviolet light curable adhesive. As a result,in the embodiment shown in FIGS. 14 and 15, the sheath 410, which may beformed of, e.g., PELLETHANE®, may be bonded to the second layer 620,which may be formed of a material that is not lubricious (e.g., PEBAX®or other non-fluorinated material).

In the embodiments shown in FIGS. 16-21 described below, the first layer610 of the instrument shaft section 60 may cover substantially theentire second layer 620. The portion 414 or 416 of the sheath 410, whichmay be formed of, e.g., PELLETHANE®, may be bonded to the inner tubularportion 640 of the instrument shaft assembly 60, which may be formed ofa material that is not lubricious (e.g., nylon or other non-fluorinatedmaterial).

In the embodiment shown in FIGS. 16 and 17, the proximal end portion ofthe sheath 410 may extend over the distal end portion of the first layer610 of the instrument shaft section 60 to form the junction 650 betweenthe sheath 410 and the first layer 610. An intermediate portion 416 ofthe sheath 410 may overlie and be bonded to the exposed portion of theinner tubular portion 640 of the instrument shaft assembly 60 (e.g., theportion of the inner tubular portion 640 that is radially expanded dueto the insertion of the tubular portion 530 of the proximal adapter500). The intermediate portion 416 may be bonded using an adhesive, suchas a cyanoacrylate, a two-part epoxy, or an ultraviolet light curableadhesive.

Also, at the junction 650 formed by the meeting of the proximal endportion of the sheath 410 with the distal end portion of the first layer610, the proximal end portion of the sheath 410 may form a seal with thefirst layer 610. For example, the sheath 410 may be formed of astretchable or elastic material (e.g., PELLETHANE®) that provides acompressive radial pressure on the overlapped portion of the first layer610. Alternatively, or in addition, the distal end portion of the firstlayer 610 may be treated (e.g., plasma treated, chemically etched, etc.)and bonded to the proximal end portion of the sheath 410 (e.g., using anadhesive). As another alternative, the distal end portion of the firstlayer 610 and/or the proximal end portion of the sheath 410 may beroughened to increase the surface areas of the respective portions, andthe roughened portions may be bonded together (e.g., using an adhesive).Roughening the respective portions may provide increased surface area(e.g., valleys) for the adhesive to contact.

According to another embodiment, as shown in FIGS. 18 and 19, the firstlayer 610 of the instrument shaft section 60 may include a distal endportion that extends past the second and third layers 620 and 630 in thedistal direction, without covering a distal end portion of the innertubular portion 640. The distal end portion of the first layer 610 thatextends past the second and third layers 620 and 630 may form thejunction 650 between the sheath 410 and the first layer 610 of theinstrument shaft section 60.

The proximal end portion 414 of the sheath 410 may extend over thedistal end portion of the inner tubular portion 640. The proximal endportion 414 of the sheath 410 may meet and abut the distal edge of thesecond layer 620 and/or a distal edge of the third layer 630. Theintermediate portion 416 of the sheath 410 may overlie and be bonded tothe exposed portion of the inner tubular portion 640 of the instrumentshaft assembly 60 (e.g., the portion of the inner tubular portion 640that is radially expanded due to the insertion of the tubular portion530 of the proximal adapter 500). The intermediate portion 416 of thesheath 410 may be bonded to the inner tubular portion 640, e.g. using anadhesive, such as a cyanoacrylate, a two-part epoxy, or an ultravioletlight curable adhesive.

Also, at the junction 650 formed by the meeting of the proximal endportion of the sheath 410 with the distal end portion of the first layer610, the proximal end portion of the sheath 410 may form a seal with thefirst layer 610. For example, the first layer 610 may be formed of astretchable or elastic material (e.g., FEP) that provides a compressiveradial pressure on the overlapped portion of the sheath 410.Alternatively, other methods as described above, e.g., plasma treatment,chemical etching, surface roughening and bonding, etc., may be used toform the seal.

According to another embodiment, as shown in FIGS. 20 and 21, the firstlayer 610 of the instrument shaft section 60 may include a distal endportion that extends past the second and third layers 620 and 630 in thedistal direction, without covering a distal end portion of the innertubular portion 640, similar to the embodiment shown in FIGS. 18 and 19.For example, to form the first layer 610 so that the distal end portionextends past the second and third layers 620 and 630 in the distaldirection, distal end portions of the second and third layers 620 and630 may be removed prior to forming the first layer 610 on the secondlayer 620 (e.g., by centerless grinding or other removal method).Alternatively, other methods may be used to provide the first layer 610that extends past the second and third layers 620 and 630 in the distaldirection.

The distal end portion of the first layer 610 that extends past thesecond and third layers 620 and 630 may form the junction 650 betweenthe sheath 410 and the first layer 610 of the instrument shaft section60. However, instead of overlapping the sheath 410 as shown in theembodiment shown in FIGS. 18 and 19, the first layer 610 may meet andabut a proximal edge of the sheath 410 to form the junction 650 betweenthe sheath 410 and the first layer 610 of the instrument shaft section60. The proximal end portion 414 of the sheath 410 may overlies theexposed portion of the inner tubular portion 640 and may be bonded tothe inner tubular portion 640, e.g. using an adhesive, such as acyanoacrylate, a two-part epoxy, or an ultraviolet light curableadhesive.

The distal end portion of the first layer 610 that extends past thesecond and third layers 620 and 630 may also overlie the exposed portionof the inner tubular portion 640. The distal end portion of the firstlayer 610 may form a seal with the inner tubular portion 640. Forexample, the distal end portion of the first layer 610 may be bonded tothe inner tubular portion 640, e.g. using an adhesive, such as acyanoacrylate, a two-part epoxy, or an ultraviolet light curableadhesive. Alternatively, the first layer 610 may be formed of astretchable or elastic material (e.g., FEP) that provides a compressiveradial pressure on the overlapped portion of the inner tubular portion640. Alternatively, other methods as described above, e.g., plasmatreatment, chemical etching, surface roughening and bonding, etc., maybe used to form the seal.

As a result, in an embodiment in which the third layer 630 is formed ofstainless steel braid or other braided configuration of electricallyconductive material, the third layer 630 may be provided at a distancefrom the junction 650 between the sheath 410 and the first layer 610 ofthe instrument shaft section 60, thereby assisting in preventingelectrons from arcing through the junction 650 and being transmittedthrough the third layer 630. Providing the third layer 630 at a distancefrom the junction 650 may also assist in securing any wires in the thirdlayer 630 (which may also be ground down) under the first layer 610,e.g., so that the wires do not extend through the junction 650 andscratch the patient, guide tube, or other structure for receiving theinstrument assembly 10.

FIG. 22 illustrates a medical device 710, according to an exemplaryembodiment. Medical device 710 may be configured for use with a surgicalmethod, including a therapeutic or diagnostic procedure. For example,medical device 710 may be configured for use with an endoscope, alaparoscope, a utereroscope, a guide tube, an access catheter, or anyother type of device configured to access a patient's body. Medicaldevice 710 may be used for procedures within or adjacent to various bodyorgans, such as, an esophagus, a heart, a stomach, a pelvic area, abladder, an intestine, or any other portion of a gastrointestinal,urinary, pulmonary tract, or body.

Medical device 710 may be configured for insertion into a patient's bodythrough an anatomical opening. In some embodiments, medical device 710may be used in natural orifice transluminal endoscopic surgery (NOTES)procedures or percutaneous procedures such as single incisionlaparoscopic surgical (SILS) procedures. Accordingly, medical device 710may be shaped and sized for placement into a patient via a body cavityor an incision.

Medical device 710 may include a handle portion 712, a shaft 714, anend-effector assembly 716, and a securing member 718. Shaft 714 may havea proximal end 720 and a distal portion 722. For purposes of thisdisclosure, “proximal” refers to the end closer to the device operatorduring use, and “distal” refers to the end further from the deviceoperator during use. Handle portion 712 may be disposed at proximal end720 of shaft 714. Handle portion 712 may be any suitable, known handleincluding spool-type handles or scissor-type handles. As shown in FIG.22, end-effector assembly 716 may be aligned with and connected todistal portion 722 of shaft 714.

Medical device 710 is shown in FIG. 23 in a detached configuration,whereby end-effector assembly 716 is shown separated from distal portion722 of shaft 714. As described herein, end-effector assembly 716 anddistal portion 722 of shaft 714 are configured for releasableengagement. Specifically, end-effector assembly 716 may be connected todistal portion 722 of shaft 714 by securing member 718 to allow a userto control movement, actuation, and/or operation of end-effectorassembly 716 via handle portion 712. End-effector assembly 716 may alsobe disconnected from distal portion 722 of shaft 714 so that otherend-effector assemblies (either the same or different types) may beconnected to distal portion 722 of shaft 714.

In some embodiments, handle portion 712 and shaft 714 may be reusableand end-effector assembly 716 may be disposable. Multiple end-effectorassemblies, having different end-effectors, may be used interchangeablywith a single shaft 714 and handle portion 712. It is contemplated thatthe various end-effector assemblies could be provided together in kitform.

Shaft 714 may be a flexible or rigid tube, made from any suitablebiocompatible material known to one of ordinary skill in the art. Suchmaterials may include, but are not limited to, rubber, silicon,plastics, stainless steel, metal-polymer composites, and metal alloys ofnickel, titanium, copper cobalt, vanadium, chromium, and iron. In oneembodiment, the material forming shaft 714 may be a superelasticmaterial such as nitinol, which is a nickel-titanium alloy. In someembodiments, shaft 714 may include layers of different materials andreinforcements such as braiding or coiling within the wall of shaft 714.Shaft 714 may have any cross-sectional shape and/or configuration andmay be any desired dimension that can be received in a body cavity. Insome embodiments, shaft 714 may be made of, or coated with, a polymericor lubricious material to enable medical device 710 to pass through abody cavity with ease. Additionally, shaft 714 may be steerable and mayhave areas of different flexibility or stiffness to promote steerabilitywith the body cavity. Steerability may, for example, be controlled bywires.

Shaft 714 may include a lumen 724 extending distally from proximal end720 of shaft 714 to distal portion 722 of shaft 714. It is to beunderstood that lumen 724 may have any size, cross-sectional area,shape, and/or configuration. An elongate member 726 may be disposed inlumen 724, and may be configured to move relative to shaft 714. Elongatemember 726 may include a proximal end (not shown) and a distal end 728,and may comprise malleable, flexible, and/or rigid portions. In someembodiments, elongate member 726 may be a cable, wire, or similarlyflexible material extending distally from handle portion 712 to distalportion 722. Elongate member 726 may have any desired cross-sectionalshape and/or configuration that can be received within lumen 724 ofshaft 714.

As shown in FIGS. 2 and 5C, distal end 728 of elongate member 726 mayextend into distal portion 722 of shaft 714 and may define a firstfitting 730. In some embodiments, first fitting 730 may have an L-shapedcross-sectional configuration with a first groove 730 a and a firstenlargement 730 b.

As shown in FIG. 24A, end-effector assembly 716 may be providedseparately from shaft 714 and handle portion 712, and may include anassembly of multiple components including a clevis 734, a pair ofend-effectors 736, and an actuator 738.

Clevis 734 may be, for example, machined or formed as a unitary mold orcast member, or may be stamped from a steel sheet and formed (by e.g.,rolling) into an appropriate configuration. Clevis 734 may include aproximal portion 740 and a pair of arms 742 extending from proximalportion 740. Proximal portion 740 of clevis 734 and distal portion 722of shaft 714 may have complementary shapes and/or configurations. In anexemplary embodiment, proximal portion 740 of clevis and distal portion722 of shaft 714 may each form half-cylindrical portions. It iscontemplated that proximal portion 740 of clevis 734 and distal portion722 of shaft 714 may form any other set of complementary shapes and/orconfigurations, including lock and key configurations.

Arms 742 of clevis 734 may extend distally from proximal portion 740.Arms 742 may be substantially similar in shape, however, they may alsohave different shapes or configurations. Each arm 742 may have an axlehole 744 for receiving an axle pin 743. The pair of end-effectors 736may be inserted in a slot between arms 742 and mounted to clevis 734 byaxle pin 743. In the illustrated embodiment, the pair of end-effectors736 may be graspers. It is contemplated, however, that the pair ofend-effectors 736 may be cutting blades, forceps, graspers, dissectors,scissors, biopsy forceps, or other types of tools.

As illustrated in FIG. 24B, proximal portion 740 of clevis 734 mayinclude a throughhole 749 which receives actuator 738. Actuator 738 mayhave a proximal end 752 and a pair of arms 750 extending distally fromproximal end 752 of actuator 738. Proximal end 752 of actuator 738 mayextend into proximal portion 740 of clevis 734, and may include a secondfitting 732 configured to be aligned with and coupled to first fitting730. In some embodiments, second fitting 732 may have an L-shapedcross-sectional configuration with a second groove 732 a and a secondenlargement 732 b, with similar sizes, shapes, and/or configurations asfirst groove 730 a and first enlargement 730 b of first fitting 730.Second enlargement 732 b may be received in first groove 730 a and firstenlargement 730 b may be received in second groove 732 a, so as tocouple first fitting 730 and second fitting 732. It will be appreciatedthat any number of tabs and/or protrusions may be disposed on firstfitting 730 and second fitting 732 to fit, snap, or connect into acomplementary recess or hole in second fitting 732 and first fitting730.

In some embodiments, first fitting 730 and second fitting 732 may form aball and socket coupling configuration. In particular, first fitting 730or second fitting 732 may form a ball and the other of first fitting 730and second fitting 732 may form a socket. In other embodiments, firstfitting 730 and second fitting 732 may have a dove-tail, detent pin, orsnap ring designs. It is contemplated that first fitting 730 and secondfitting 732 may have any other set of complementary shapes,configurations, and/or designs to facilitate coupling of first fitting730 and second fitting 732.

In one embodiment, arms 750 of actuator 738 may extend into a slotformed between arms 742 of clevis 734. Arms 750 may be substantiallysimilar in shape, however, they may have different shapes orconfigurations. A tang 746 of each end-effector 736 may be disposedbetween arms 750 of actuator 738. As shown in FIG. 24C, each endeffector 736 may include a slot 747 formed in tang 746. A pin 751 mayextend through slot 747 to mount end effectors 736 to arms 750 ofactuator 738. When pin 751 is in a proximalmost position in slot 747 ofeach end effector 736, the pair of end-effectors 736 may be in a closedconfiguration. Distal movement of actuator 738 may cause pin 751 to ridedistally in slot 747. In doing so, the pair of end-effectors 736 maypivot about pin 743 to translate the pair of end-effectors 736 to anopen configuration.

Referring to FIG. 25, securing member 718 may comprise a tube formed ofany rigid, malleable, or flexible material. In one embodiment, thematerial forming securing member 718 may be a stainless steel sleeve ora superelastic material such as nitinol, which is a nickel-titaniumalloy. Securing member 718 may have a shape such as a cylindrical shape,and may be sized to conform to an exterior 754 of device 710. In someembodiments, securing member 718 may fit around a portion of theperimeter of device 710 without completely extending around the entirecircumference of device 710. It is contemplated, that securing member718 may have any other shape, size, cross-sectional area, and/orconfiguration. In the exemplary embodiment illustrated in FIG. 25,securing member 718 is disposed on an exterior of shaft 714, however,securing member 718 may be provide separately from device 710 untilconnection of shaft 714 to end-effector assembly 716, or may be disposedon clevis 734 of end-effector assembly 716 prior to connection. Securingmember 718 may include cut out sections laser cut into securing member718. The cut out sections may have any size and/or shape, and mayenhance the flexibility and/or grip of securing member 718.

Securing member 718 may have a proximal end 756 and a distal end 758.Proximal end 756 of securing member 718 may be located closer to thedistal portion 722 than a proximal end 720 of shaft 714. Distal end 758of securing member 718 may include a retainer 760 having a recess 761configured to receive protrusion 762 on proximal portion 740 of clevis734. In other embodiments, securing member 718 may include a protrusionto be received by a recess on an exterior surface of proximal portion740 of clevis 734. Various other coupling mechanisms are alsocontemplated such as, for example, an external cuff or tab to locksecuring member 718 relative to proximal portion of clevis 734.

Referring to FIGS. 5A and 5B, medical device 710 may be assembled byaligning proximal portion 740 of clevis 734 with distal portion 722 ofshaft 714. In particular, the half-cylindrical portions (i.e., proximalportion 740 and distal portion 722) may be flush mounted together toform a substantially cylindrical joint 764. In this configuration,second fitting 732 may be aligned with first fitting 730 of elongatemember 726 so that groove 732 a of second fitting may receiveenlargement 730 b of first fitting 730 and enlargement 732 b of secondfitting 732 may be received in groove 730 a of first fitting 730. Insome embodiments, there may be some flexibility between the shapes offirst fitting 730 and second fitting 732 to allow friction fit or somedeformation when first fitting 730 is aligned and coupled to secondfitting 732.

Securing member 718 may move distally relative to distal portion 722 ofshaft 714 and end effector assembly 716 when proximal portion 740 ofclevis 734 and distal portion 722 of shaft 714 are aligned to formsubstantially cylindrical joint 764. In particular, securing member 718may slide distally from a first position as shown in FIG. 26A to asecond position as shown in FIG. 26B. In the first position, securingmember 718 may be positioned proximal to distal portion 722 of shaft714. In the second position, a substantial portion of securing member718 may be disposed around substantially cylindrical joint 764.

End-effector assembly 716 may remain in a fixed position relative todistal portion 722 of shaft 714 as securing member 718 is moved from thefirst position to the second position. In some embodiments, a rim 766may be provided on clevis 734 to limit distal movement of securingmember 718 beyond the second position. In some embodiments, a stop (notshown) may also be provided on shaft 714 to limit proximal movement ofsecuring member 718 beyond the first position.

As illustrated in FIG. 26C, when securing member 718 is in the secondposition, recess 761 of retainer 760 may receive protrusion 762 onproximal portion 740 of clevis 734 to connect end-effector assembly 716to distal portion 722 of shaft 714. Retainer 760 and protrusion 762 mayform a snap-fit connection.

In some embodiments, protrusion 762 may be shaped to facilitate quickconnection of retainer 760 and protrusion 762. In particular, protrusion762 may have a proximally facing surface 762 a having a moderate slopeto facilitate distal movement of retainer 760 over protrusion 762 so asto connect retainer 760 to protrusion 762. In addition, distally facingsurface 762 b may have a greater slope than proximally facing surface762 a such that a force required to remove protrusion 762 from recess761 of retainer 760 is greater than the force required to slide retainer760 over protrusion 762. In this manner, end-effector assembly 716 mayremain connected during use. In some embodiments, surfaces 762 a and 762b may have notches to better engage retaining 60. It is contemplatedthat retainer 760 and protrusion 762 may have a tight friction enhancedfit or, alternatively, may fit together with slight deformation ofretainer 760 and protrusion 762 to enhance engagement.

When protrusion 762 is received in recess 761 of retainer 760, a radialforce may be exerted on first fitting 730 and second fitting 732 so asto couple first fitting 730 and second fitting 732. A user can thenmanipulate elongate member 726 at handle portion 712 to move elongatemember 726 and actuator 30 relative to lumen 724 of shaft 714 andthroughhole 749 of clevis 734, thereby controlling movement, actuation,and/or operation of the pair of end-effectors 736. Additional elementssuch as spring washers may be provided to bias end-effector assembly 716against the distal portion 722 of shaft 714 or vice versa to facilitateengagement of end effector assembly 716 to distal portion 722 of shaft714, take up tolerances, and provide pre-load to ensure a fully engagedand locked assembly.

A user may apply an axial force such as a proximally directed force tosecuring member 718 to slide securing member 718 from the secondposition (FIG. 25B) to the first position (FIG. 25A), so as to releaseprotrusion 762 from recess 761 of retainer 760 and disconnectend-effector assembly 716 from distal portion 722 of shaft 714. Otherend-effector assemblies (either the same or different types) may then beconnected to distal portion 722 of shaft 714.

In another embodiment, securing member 718 may be made of a flexiblematerial that can change cross-sectional shape to disconnectend-effector assembly 716 from distal portion 722. In this embodiment,securing member 718 may have a substantially circular cylindricalcross-sectional shape in the first position. Securing member may bemoved distally from the first position to the second position, andretainer 760 may receive protrusion 762 to connect end-effector assembly716 to distal portion 722.

In order to disconnect end-effector assembly 716 from distal portion722, a user may squeeze lateral portions of securing member 718 so as tochange the shape of securing member 718 from the substantially circularcylindrical cross-sectional shape to a substantially vertical oblongcylindrical cross-sectional shape. By doing so, retainer 760 may releaseprotrusion 762. In this embodiment, securing member 718 may be flexibleso as to return to the substantially circular cross-sectional shape.Securing member 718 may then be moved proximally from the secondposition to the first position. In the first position, end-effectorassembly 716 may be removed and other end-effector assemblies (eitherthe same or different types) may be connected to distal portion 722 ofshaft 714. It is contemplated that clevis 734 may have scallops tofacilitate deformation of securing member 718, and securing member 718may have dents, taps, or other structures to aid in grasping andsqueezing securing member 718.

In yet another embodiment, securing member 718 may be rotated relativeto end-effector assembly 716 and distal portion 722 of shaft 714 tocouple and/or decouple securing member from shaft 714. Various othertypes of movements of securing member 718 are also contemplated such as,for example, snapping securing member 718 around substantiallycylindrical joint 764, fitting securing member 718 around substantiallycylindrical joint 764 with a screw thread, or wrapping securing member718 around substantially cylindrical joint 764.

Alternative non-limiting examples of end-effector assemblies havingvarious shapes and/or distal configurations are shown in FIGS. 6A and6B. In the end-effector assembly 716 a depicted in FIG. 27A, the pair ofend-effectors 736 a may be scissors. Scissors may curve to the right orleft for use by an right-handed or left-handed operator. In theend-effector assembly 716 b depicted in FIG. 27B, the pair ofend-effectors 736 b may be dissectors. Dissectors 736 b may curve to theright or left for use by a right-handed or left-handed operator.

The disclosed medical device may have certain advantages. As notedabove, the disclosed medical device 710 may be configured so thatmultiple end-effector assemblies, having different end-effectors, may beused interchangeably with a single shaft 714 and handle portion 712.This may provide a surgeon with greater capabilities during a procedure.Specifically, surgeons may have the flexibility to create specificdevices as needed. Moreover, the various end-effector assemblies may beprovided together in kit form. This may be advantageous for hospitalinventory control, as the medical device may occupy less space in theoperating room and/or storage.

It is also contemplated that in one embodiment, the distal portion ofthe shaft 714 may include features of the proximal portion of the distaladapter 300 and the articulation links 400, and more proximal portionsof the shaft 714 may include the features of the proximal adapter 500and the instrument shaft section 60. In such an embodiment, articulationcontrol member portions similar to the articulation control memberportions 111, 112, 113, and 114 may be used to deflect the distalportion of the shaft 714.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the disclosed systems andprocesses without departing from the scope of the disclosure. Otherembodiments of the disclosure will be apparent to those skilled in theart from consideration of the specification and practice of the aspectsdisclosed herein. It is intended that the specification and examples beconsidered as exemplary only, with a true scope and spirit of thedisclosure being indicated by the following claims.

1-20. (canceled)
 21. A medical device comprising: an articulationsection comprising a plurality of links; an end effector; and an adapterextending from a proximal end to a distal end, wherein the proximal endis configured to attach to the plurality of links of the articulationsection, and the distal end is configured to attach to the end effector,the adapter including: a channel extending from the proximal end to thedistal end; and at least one side cavity having an open proximal end anda closed distal end.
 22. The medical device of claim 21, wherein the atleast one side cavity of the adapter includes two side cavities disposedopposite each other.
 23. The medical device of claim 22, wherein themedical device includes at least two articulation control members, eacharticulation control member forming a bend housed within a correspondingside cavity of the adapter.
 24. The medical device of claim 21, whereinthe proximal end of the adapter includes a mating element complementaryto a corresponding mating element of a distalmost link of thearticulation section.
 25. The medical device of claim 21, wherein thedistal end of the adapter includes a plurality of protrusions configuredto interlock with the end effector.
 26. The medical device of claim 21,wherein the medical device includes at least one articulation controlmember that passes through each link of the plurality of links of thearticulation section.
 27. The medical device of claim 21, wherein thearticulation section includes a central lumen in communication with thechannel of the adapter.
 28. The medical device of claim 21, wherein thechannel of the adapter houses a control member configured to articulatethe end effector.
 29. The medical device of claim 21, wherein the endeffector includes two jaws that pivot about a pivot point.
 30. A medicaldevice comprising: an articulation section; an end effector; and anadapter extending from a proximal end to a distal end, wherein theproximal end of the adapter is configured to attach to a distal end ofthe articulation section, and the distal end of the adapter isconfigured to attach to the end effector, the adapter including: acentral channel extending from the proximal end of the adapter to thedistal end of the adapter; and a first cavity radially outward of thechannel, the first cavity having an open proximal end and a closeddistal end; and an articulation control member including two portionsthat extend through the articulation section, the two portions joiningtogether in a bend within the first cavity of the adapter.
 31. Themedical device of claim 30, wherein the articulation section includes aplurality of links, each link defining two apertures that receive therespective two portions of the articulation control member.
 32. Themedical device of claim 30, wherein the adapter includes a second cavitydisposed a side of the adapter opposing the first cavity.
 33. Themedical device of claim 30, wherein the end effector includes two jaws,and the central channel of the adapter houses a control memberconfigured to articulate the jaws.
 34. The medical device of claim 30,wherein the end effector is adapted to transmit electrical current totissue.
 35. A medical device comprising: an articulation sectioncomprising a plurality of links; an end effector configured to grasptissue; and an adapter extending from a proximal end to a distal end,wherein the proximal end is configured to receive a distalmost link ofthe plurality of links of the articulation section, and the distal endincludes at least one protrusion configured to interlock with the endeffector, the adapter including: a channel extending from the proximalend to the distal end; and at least one cavity radially outward of thechannel.
 36. The medical device of claim 35, wherein the at least onecavity has an open proximal end and a closed distal end.
 37. The medicaldevice of claim 35, wherein the at least one cavity of the adapterincludes two cavities disposed on opposite sides of the adapter.
 38. Themedical device of claim 37, wherein the medical device includes at leasttwo articulation control members, each articulation control memberforming a bend housed within a corresponding cavity of the adapter. 39.The medical device of claim 38, wherein each articulation control memberincludes two portions that extend through the articulation section, thetwo portions joining together to form the bend.
 40. The medical deviceof claim 38, wherein the at least two articulation control members arefixedly attached to the adapter.